Partial purification and characterization of cyclic adenosine monophosphate dependent protein kinase from mycobacterium smegmatis.

Adenosine 3' 5'-monophosphate (cyclic AMP) - dependent protein kinase was purified about 42 fold from the M. smegmatis by ammonium sulphate fractionation followed by DEAE-cellulose and phosphocellulose column chromatography. SDS-PAGE revealed two prominent bands, with molecular masses of 55 KDa and 58 KDa. The enzyme preferentially utilized phosvitin and Histones as exogenous phosphate acceptor. Mg2+ ions were essential for enzyme activity, other metal ions like Ca2+, Zn2+, Co2+ and Mn2+, could not substitute for Mg2+. Inhibition of enzyme activity by thiol reagents, 5-5'-dithio bis (2-nitrobenzoic acid) and N-ethylmaleimide suggest that the cystein residues in the protein kinase might be located at or near the active site of the enzyme.